Back when PowerBars first hit the market, much was made of how handy they were for racing cyclists. They had plenty of carbs for energy, and other nutrients that (supposedly) made them more nutrient-dense than normal food. Therefore, you could (supposedly) carry more nutrition in a smaller, lighter package than what was possible with "normal" food.
But there was one "advantage" to PowerBars that I heard of from a lot of racers. That "advantage" was that PowerBars were sticky enough that you could peel the package off of the bar, and stick the bar onto your stem or top tube. Then, when you needed a bite, you could just peel the bar off of your bike and eat it, without having to deal with the wrapper.
When some racer would tout this so-called "advantage", I would glance over at my bike, with splotches of dried sweat, and snot, and who-knows what else, all over the stem and top-tube...and I would shudder.
It still kinda makes my stomach roll, a bit, to think of it.